How Can I List Files in a Directory or Subdirectories in R?

Base R offers access to directory listings through list.files() and list.dirs().

By default, list.files() lists all files in the current working directory, returning a character vector.

list.files()
[1] "file-eight.csv" "file-five.ods"  "file-four.rtf"  "file-nine.docx" "file-one.txt"  
[6] "file-seven.csv" "file-six.odt"   "file-ten.tex"   "file-three.rtf" "file-two.txt"

How Do I Specify a Directory?

Use the path = argument to specify a directory to pass to list.files().

list.files(path = '/home/jsmith/subdir/')
[1] "s-file-five.ods"  "s-file-four.rtf"  "s-file-one.txt"   "s-file-three.rtf"
[5] "s-file-two.csv"

How Do I Include Hidden Files?

The all.files = argument can be used to specify whether to expose hidden files. By default, all.files = F.

list.files(path = '/home/jsmith/subdir/')
[1] "s-file-five.ods"  "s-file-four.rtf"  "s-file-one.txt"   "s-file-three.rtf"
[5] "s-file-two.csv"

list.files(path = 'subdir/', all.files = T)
[1] "."                ".."               ".git"             "s-file-five.ods" 
[5] "s-file-four.rtf"  "s-file-one.txt"   "s-file-three.rtf" "s-file-two.csv"

Can I Exclude the "." and ".." From the Listing?

The current (".") directory and parent ("..") directory can be excluded by using the no.. = argument. By default, no.. = F.

list.files(path = 'subdir/', all.files = T, no.. = T)
[1] ".git"             "s-file-five.ods"  "s-file-four.rtf"  "s-file-one.txt"  
[5] "s-file-three.rtf" "s-file-two.csv"

How Can I List Certain Files?

The pattern = argument allows you to specify a regular expression pattern in order to return particular files.

# return CSV files in current directory
list.files(path = '.', pattern = '\\.csv$')
[1] "file-eight.csv" "file-seven.csv"

# return RTF and DOCX files in current and all subdirectories
list.files(path = '.', recursive = T, pattern = '(\\.rtf$|\\.docx)$')
[1] "file-four.rtf"           "file-nine.docx"          "file-three.rtf"         
[4] "subdir/s-file-four.rtf"  "subdir/s-file-three.rtf"

How Can I List the Full Path Name of File?

To return full path names of files, include the full.names = T argument. This works by prepending the path name to the listed files. 

list.files(path = '/home/jsmith/subdir/', full.names = T, recursive = T)
[1] "/home/jsmith/subdir/s-file-five.ods"
[2] "/home/jsmith/subdir/s-file-four.rtf"
[3] "/home/jsmith/subdir/s-file-one.txt"
[4] "/home/jsmith/subdir/s-file-three.rtf"
[5] "/home/jsmith/subdir/s-file-two.csv"